The present invention relates generally to filament winding operations, and more particularly, to a system for maintaining the mandrel in alignment with the winding machine during the filament winding operations.
Filament-wound structures of various configurations are provided by winding multiple layers of filamentary material about a mandrel. In certain types of filament-winding machines, the mandrel is supported in the necessary position for receiving the filamentary material by rollers or pads. During the winding operation, the mandrel is displaced from its original position with respect to the winding apparatus as a filamentary material is wound about the mandrel due to such conditions such as the build-up of the filamentary material about the mandrel, variations in the winding thickness on various surface portions of the mandrel, or changing the orientation of the mandrel. Inasmuch as the mandrel must be maintained within close tolerances to a selected position with respect to the winding machine for producing a filament winding of accurate dimensions and specified structural characteristics, the mandrel must be often re-aligned during the winding operation to maintain, as close as possible, the original position of the mandrel with respect to the winding machine.
Previously, the re-aligning of the mandrel to the winding machine required that the winding machine be stopped and the position of the filamentary material on the mandrel be determined with a scale. The mandrel position was then adjusted until the filamentary material was capable of being deposited on the mandrel in a desired manner on the mandrel. This technique was slow and depended primarily upon the skill of the operator to re-align the mandrel for the proper reception of the filamentary material. An improvement over the above technique for aligning the mandrel used as a reference on the mandrel and a dial indicator for showing the position of the reference pin with respect to the proper position of the mandrel in the winding machine. The winding machine is periodically stopped and the mandrel was then manually moved to the desired position and the machine re-started. Both of these previous mandrel aligning techniques were fairly inaccurate and highly inefficient since the winding machine must be stopped at various intervals during the winding operation in order to re-align the mandrel for assuring the fabrication of a properly wound filament structure.